Olive Cultivation in the Southern Hemisphere: Flowering, Water Requirements and Oil Quality Responses to New Crop Environments

Abstract

Olive ( Olea europaea L.) is a crop well adapted to the environmental conditions prevailing in the Mediterranean Basin. Nevertheless, the increasing international demand for olive oil and table olives in the last two decades has led to expansion of olive cultivation in some countries of the southern hemisphere, notably in Argentina, Chile, Perú and Australia. While the percentage of world production represented by these countries is still low, many of the new production regions do not have typical Mediterranean climates, and some are located at subtropical latitudes where there is relatively little information about crop function. Thus, the primary objective of this review was to assess recently published scientific literature on olive cultivation in these new crop environments. The review focuses on three main aspects: (a) chilling requirements for flowering, (b) water requirements and irrigation management, and (c) environmental effects on fruit oil concentration and quality. In many arid and semiarid regions of South America, temperatures are high and rainfall is low in the winter and early spring months compared to conditions in much of the Mediterranean Basin. High temperatures have often been found to have detrimental effects on olive flowering in many olive cultivars that have been introduced to South America, and a better understanding of chilling requirements is needed. Lack of rainfall in the winter and spring also has resulted in an urgent need to evaluate water requirements from the flower differentiation period in the winter to early fruit bearing. Additionally, in some olive growing areas of South America and Australia, high early season temperatures affect the timing of phenological events such that the onset of oil synthesis occurs sooner than in the Mediterranean Basin with most oil accumulation taking place in the summer when temperatures are very high. Increasing mean daily temperatures have been demonstrated to decrease fruit oil concentration (%) and negatively affect some aspects of oil quality based on both correlative field studies and manipulative experiments. From a practical standpoint, current findings could be used as approximate tools to determine whether the temperature conditions in a proposed new growing region are appropriate for achieving sustainable oil productivity and quality.

Olive oil characterization of cv. ‘Arauco’ harvested at different times in areas with early frost in Mendoza, Argentina

“…New plantations using foreign cultivars – particularly Arbequina – were established at a high density (more than 300 trees ha −1 ) and adapted to mechanized harvesting. However, some foreign cultivars grown in many regions of Argentina have showed poor adaptation in terms of oil production and quality compared with their original cultivation sites …”

“…The mean daily minimum temperature in Mendoza during autumn (olive harvest season) is 7.5 °C with a high probability of early frost occurrence . Cold‐weather conditions differentiate olive growing in Mendoza from olive growing in the warm valleys of northwestern Argentina including San Juan, La Rioja, and Catamarca (28–31 °S) provinces, where mean daily minimum temperature ranges between 10.9 °C and 13.0 °C in autumn with a lower probability of early frost occurrence …”

Assessment of Vibrational Spectroscopy Performance in Geographical Identification of Virgin Olive Oils: A World Level Study

“…This diversity depends on each geographical area. Thus, for instance, in Italy, there is a large number of cultivars and the commercialized oils are blends of some of them. New agricultural practices as well as new/old cultivars: the implementation of new agricultural practices plays an important role in the chemical composition of oils . So these variables were also considered.…”

“…New agricultural practices as well as new/old cultivars: the implementation of new agricultural practices plays an important role in the chemical composition of oils . So these variables were also considered.…”

Drip Irrigation Elevated Olive Productivity in Southwest China

“…Olive yield will be negatively affected by water shortages during these periods. In the Mediterranean basin, the rainfall during the winter is relatively high and precludes the need to irrigate for olive flowering and subsequent fruit set (Torres et al, 2017). This is different from the climate in southwestern China.…”